<template>
  <div class="goods">
    <div class="menu-wrapper" ref="menuWrapper">
      <ul>
        <li v-for="(item,index) in goods" :key="item.id" class="menu-item" :class="{'current': currentIndex === index}" @click="seletcMenu(index,$event)"> 
          <span class="text border-1px">
            <span v-show="item.type>0" class="icon" :class="classMap[item.type]"></span>  {{ item.name }}
          </span>
        </li>
      </ul>
    </div>
    <div class="foods-wrapper" ref="foodsWrapper">
      <ul>
        <li v-for="item in goods" :key="item.id" class="food-list food-list-hook">
          <h1 class="title">{{ item.name }}</h1>
          <ul>
            <li @click="selectFood(food,$event)" v-for="food in item.foods" :key="food.id" class="food-item border-1px">
              <div class="icon">
                <img width="57" height="57" :src="food.icon">
              </div>
              <div class="content">
                <h2 class="name">{{ food.name }}</h2>
                <p class="desc">{{ food.description }}</p>
                <div class="extra">
                  <span class="count">月售{{ food.sellCount }}份</span><span>好评率{{ food.rating }}%</span>
                </div>
                <div class="price">
                  <span class="new">￥{{ food.price }}</span><span class="old" v-show="food.oldPrice">￥{{ food.oldPrice }}</span>
                </div>
                <div class="cartcontrol-wrapper">
                  <cartcontrol :food="food" @cart-add="cartAdd"></cartcontrol>
                </div>
              </div>
            </li>
          </ul>
        </li>
      </ul>
    </div>
    <shopcart ref="shopcart" :selectFoods="selectFoods"></shopcart>
    <food :food="selectedFood" ref="food" @cart-add="cartAdd"></food>
  </div>
</template>

<script>
import BScroll from 'better-scroll'
import shopcart from '../shopcart/shopcart.vue'
import cartcontrol from '../cartconcontrol/cartcontrol.vue'
import food from '../food/food.vue'
export default {
    props: {
      seller: {
        type:  Object
      }
    },
    data() {
      return {
        goods: [],
        listHeight: [],
        scrollY: 0,
        selectedFood: {}
      }
    },
    computed: {
      currentIndex(){
        for(var i=0;i<this.listHeight.length;i++){
          var height1 = this.listHeight[i]
          var height2 = this.listHeight[i+1]
          if(!height2 || this.scrollY >= height1 && this.scrollY < height2){
            return i
          }
        } 
        return 0
      },
      selectFoods(){
        var foods = []
        this.goods.forEach((good) => {
          good.foods.forEach((food) =>{
            if(food.count){
              foods.push(food)
            }
          })
        })
        return foods
      }
    },
    created(){
      this.$http.get('/api/goods').then(result => {
        if(result.body.errno === 0){
          this.goods = result.body.data
          this.$nextTick(() => {
            this._initScroll()
            this._calculateHeight()
          })
        }
      }),
      this.classMap = ['decrease','discount','special','invoice','guarantee'] 
    },
    methods: {
      seletcMenu(index,event){
        if(!event._constructed){
          return
        }
        var foodList = this.$refs.foodsWrapper.getElementsByClassName('food-list-hook')
        var el = foodList[index]
        this.foodsScroll.scrollToElement(el,300)
      },
      selectFood(food,event){
        if(!event._constructed){
          return
        }
        this.selectedFood = food
        this.$refs.food.show()
      },
      cartAdd(target){  
        this.$nextTick(() => { // 体验优化，异步执行小球下落动画
          this.$refs.shopcart.drop(target)
        })
      },
      _initScroll(){
        this.meunScroll = new BScroll(this.$refs.menuWrapper,{ click:true })

        this.foodsScroll = new BScroll(this.$refs.foodsWrapper,{ click:true,probeType:3 })

        this.foodsScroll.on('scroll',(pos) => {
          this.scrollY = Math.abs(Math.round(pos.y))
        })
      },
      _calculateHeight(){
        var foodList = this.$refs.foodsWrapper.getElementsByClassName('food-list-hook')
        var height = 0
        this.listHeight.push(height)
        for(var i=0;i<foodList.length;i++){
          var item = foodList[i]
          height += item.clientHeight
          this.listHeight.push(height)
        }
      }
    },
    components: {
      'shopcart': shopcart,
      'cartcontrol': cartcontrol,
      'food' : food
    }
}
</script>

<style lang="stylus" rel="stylesheet/stylus">
  @import "../../common/stylus/mixin.styl"

  .goods
    display: flex
    position: absolute
    top: 174px
    bottom: 46px
    width: 100%
    overflow: hidden
    .menu-wrapper
      flex: 0 0 80px
      width: 80px
      background: #f3f5f7
      .menu-item
        display: table
        height: 54px
        width: 56px
        padding: 0 12px
        line-height: 14px
        &.current
          position: relative
          z-index: 10
          margin-top: -1px
          background: #fff
          font-weight: 700
          .text
            border-none()
        .icon
          display: inline-block
          width: 16px
          height: 16px
          vertical-align: top
          margin-right: 0
          background-size: 16px 16px
          background-repeat: no-repeat
          &.decrease
              bg-image('decrease_3')
          &.discount
              bg-image('discount_3')
          &.guarantee
              bg-image('guarantee_3')
          &.invoice
              bg-image('invoice_3')
          &.special
              bg-image('special_3')
        .text
          display: table-cell
          width: 56px
          vertical-align: middle
          border-1px(rgba(7,17,27,0.1))
          font-size: 12px
    .foods-wrapper
      flex: 1
      .title
        padding-left: 14px
        height: 26px
        line-height: 26px
        border-left: 2px solid #d9ddel
        font-size: 12px
        color: rgb(147,153,159)
        background: #f3f5f7
      .food-item
        display: flex
        margin: 18px
        padding-bottom: 18px
        border-1px(rgba(7,17,27,0.1))
        &:last-child
          border-none()
          margin-bottom: 0
        .icon
          flex: 0 0 57px
          margin-right: 10px
        .content
          flex: 1
          .name
            margin: 2px 0 8px 0
            height: 14px
            line-height: 14px
            font-size: 14px
            color: rgb(7,17,27)
          .desc,.extra
            margin-bottom: 8px
            line-height: 10px
            font-size: 10px
            color: rgb(147,153,159)
          .extra
            .count
              margin-right: 12px
          .desc
            line-height: 12px
            margin-bottom: 8px
          .price
            font-weight: 700
            line-height: 24px
            .new
              margin-right: 8px
              font-size: 14px
              color: rgb(240,20,20)
            .old
              text-decoration: line-through
              font-size: 10px
              color: rgb(147,153,159)
        .cartcontrol-wrapper
          position: absolute
          right: 0
          bottom: 0
</style>